Study on the mechanism of mitigating radiation damage by improving the hematopoietic system and intestinal barrier with Tenebrio Molitor peptides

Abstract

ABSTRACT: Research on plant and animal peptides has garnered significant attention, but there is a lack of studies on the functional properties of Tenebrio molitor peptides, particularly in relation to their potential mitigating effect on radiation damage and the underlying mechanisms. This study aimed to explore the protective effects of Tenebrio molitor peptides against radiation-induced damage. Mice were divided into five groups: normal, radiation model, and low, medium, and high-dose Tenebrio molitor peptide (TMP) groups (0.15 g/kg BW, 0.30 g/kg BW, 0.60 g/kg BW). Various parameters such as blood cell counts, bone marrow DNA content, immune organ indices, serum levels of D-lactic acid, diamine oxidase (DAO), endotoxin (LPS), and inflammatory factors were assessed at 3 ，15 days post gamma irradiation. Additionally, intestinal tissue morphology was examined through HE staining, RT-qPCR experiments were conducted to analyze the expression of inflammatory factors in the intestine, and immunohistochemistry was utilized to evaluate the expression of tight junction proteins ZO-1 and Occludin in the intestine. The findings revealed that high-dose TMP significantly enhanced the hematopoietic system function in mice post radiation exposure, leading to increased spleen index, thymus index, blood cell counts, and bone marrow DNA production (p<0.05). Moreover, TMP improved intestinal barrier integrity and reduced intestinal permeability. Mechanistic insights suggested that these peptides may safeguard intestinal barrier function by downregulating the gene expression of inflammatory factors TNF-α, IL-1β, and IL-6, while upregulating the expression of tight junction proteins ZO-1 and Occludin (p<0.05). Overall, the supplementation of TMP mitigates radiation-induced intestinal damage by enhancing the hematopoietic system and intestinal barrier, offering valuable insights for further investigations into the mechanisms underlying the protective effects of these peptides against ionizing radiation.